CVE-2026-31705
Gravedad CVSS v3.1:
CRÍTICA
Tipo:
CWE-787
Escritura fuera de límites
Fecha de publicación:
01/05/2026
Última modificación:
06/05/2026
Descripción
*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
ksmbd: fix out-of-bounds write in smb2_get_ea() EA alignment<br />
<br />
smb2_get_ea() applies 4-byte alignment padding via memset() after<br />
writing each EA entry. The bounds check on buf_free_len is performed<br />
before the value memcpy, but the alignment memset fires unconditionally<br />
afterward with no check on remaining space.<br />
<br />
When the EA value exactly fills the remaining buffer (buf_free_len == 0<br />
after value subtraction), the alignment memset writes 1-3 NUL bytes<br />
past the buf_free_len boundary. In compound requests where the response<br />
buffer is shared across commands, the first command (e.g., READ) can<br />
consume most of the buffer, leaving a tight remainder for the QUERY_INFO<br />
EA response. The alignment memset then overwrites past the physical<br />
kvmalloc allocation into adjacent kernel heap memory.<br />
<br />
Add a bounds check before the alignment memset to ensure buf_free_len<br />
can accommodate the padding bytes.<br />
<br />
This is the same bug pattern fixed by commit beef2634f81f ("ksmbd: fix<br />
potencial OOB in get_file_all_info() for compound requests") and<br />
commit fda9522ed6af ("ksmbd: fix OOB write in QUERY_INFO for compound<br />
requests"), both of which added bounds checks before unconditional<br />
writes in QUERY_INFO response handlers.
Impacto
Puntuación base 3.x
9.80
Gravedad 3.x
CRÍTICA
Productos y versiones vulnerables
| CPE | Desde | Hasta |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 5.15.145 (incluyendo) | 5.16 (excluyendo) |
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 6.1.71 (incluyendo) | 6.2 (excluyendo) |
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 6.6 (incluyendo) | 6.6.136 (excluyendo) |
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 6.7 (incluyendo) | 6.12.84 (excluyendo) |
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 6.13 (incluyendo) | 6.18.25 (excluyendo) |
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 6.19 (incluyendo) | 7.0.2 (excluyendo) |
Para consultar la lista completa de nombres de CPE con productos y versiones, ver esta página
Referencias a soluciones, herramientas e información
- https://git.kernel.org/stable/c/30010c952077a1c89ecdd71fc4d574c75a8f5617
- https://git.kernel.org/stable/c/790304c02bf9bd7b8171feda4294d6e62d32ae8f
- https://git.kernel.org/stable/c/922d48fe8c19f388ffa2f709f33acaae4e408de2
- https://git.kernel.org/stable/c/98f3de6ef4efbd899348d333f0902dc4ff14380c
- https://git.kernel.org/stable/c/ffbce350c6fd1e99116ea57383b9031717e36d3b



